Could be a bad install disk/usb stick, it happened to me the other day, a simple clear cmos worked in the end.
if the bios can see the hdd i doubt a cmos clear would cure it? you have a spare pc to plug hdd into? try formatting the hdd in ntfs,windows disk might see the drive then?
you could go into diskpart and format the hdd that way, i also had to do this with my problem, but it might also be if your bios is set to ahci and missing a driver, change back to ide and try that.
to clear cmos there will either be a dedicated button on the board, or there will be three jumper pins on the board, with it written next to them, two pins will be covered, if you look in your motherboard manual it will tell you how to do it.
does your mb has a special raid controller may be windows 7 doesnt have the driver for.
try install the raid controller driver once you reach the select hdd screen
the driver will be on the cd that came with the mobo, or you can download the latest from the gigabyte website, turn your computer off when you clear cmos
did you try both ide and ahci modes in the bios?
Mode should not make a difference.
Try different sata ports and different cables.
Download a new iso for windows.
please help
did you install using a disc or usb flash drive? if usb flash drive, make sure you plug it in to usb 2.0 not usb 3.0